* {
    margin: 0;
    padding: 0;
}

.container {
    width: 1000px;
    margin: 0px auto;
    background-color: rgb(225, 250, 82);
    text-align: center;
    padding: 35px;
    box-sizing: border-box;
}

.a {
    display: inline-block;
    background-color: cyan;
    border: 8px double rgb(197, 95, 228);
    width: 300px;
    height: 300px;
    margin: 25px;
    padding: 30px;
    box-sizing: border-box;
}

.b {
    display: inline-block;
    background-color: cyan;
    border: 6px double rgb(197, 95, 228);
    width: 300px;
    height: 300px;
    margin: 25px;
    padding: 30px;
    box-sizing: border-box;
}

.c {
    display: inline-block;
    background-color: cyan;
    border: 6px double rgb(197, 95, 228);
    width: 300px;
    height: 300px;
    margin: 25px;
    padding: 30px;
    box-sizing: border-box;
}

.d {
    display: inline-block;
    background-color: cyan;
    border: 6px double rgb(197, 95, 228);
    width: 300px;
    height: 300px;
    margin: 25px;
    padding: 30px;
    box-sizing: border-box;
}